以丙烯为碳源,在700 ℃～1 200 ℃进行化学气相沉积热解炭.采用气相色谱和质谱联用对反应过程中的气体产物进行定性和半定量分析,采用磁悬浮天平实时称量反应过程中的固相产物进行动力学研究,在此基础上提出丙烯分解形成热解炭的机理.气相产物的分析结果表明:丙烯热解过程产生30多种芳香化合物,随着温度的升高,主要反应生成物由萘转变为苯;动力学研究结果表明,800 ℃～1 000 ℃的活化能为137±25 kJ/mol,生成乙炔的基元反应控制固相产物的形成.当温度高于1 000 ℃时,沉积行为由气相分子通过边界向固相表面扩散和气相成核共同控制,形成热解炭的主要物质逐渐由苯转变为不饱和碳氢化合物如乙烃,乙烯等.
Gas products and chemical vapor deposition kinetics of pyrocarbon (PyC) formed during pyrolysis of a propylene/argon mixture in the range 700-1200℃ were analyzed by out-line gas chromatography coupled with mass spectrometry and by an in-situ magnetic suspension balance,respectively.More than 30 components were identified.Benzene was the main product,substituting for naphthalene as the temperature increased.PyC was formed with an apparent activation energy of (137±25) kJ/mol,assumed to be controlled by the acetylene-forming reaction from 800℃ to 1000℃.Whereas,above 1000℃,the deposition behavior was representative of a combination between gas phase diffusion from the bulk flow to the solid surface and gas phase nucleation.Reaction models describing homogeneous gas phase PyC deposition reactions were derived.On the basis of these results,a reaction path scheme of PyC formation from propylene was proposed.
参考文献
| [1] | Savage G.Carbon-Carbon Composites[M].London:Chapman and Hall,1993:85. |
| [2] | Naslain R;Langlais F .CVD processing of ceramic-ceramic composite materials[J].Material Science Research,1986,20:145-152. |
| [3] | Vignoles GL;Langlais F;Descamps C;Mouchon A;Le Poche H;Reuge N;Bertrand N .CVD and CVI of pyrocarbon from various precursors[J].Surface & Coatings Technology,2004(0):241-249. |
| [4] | Becker A.;Huttinger KJ. .Chemistry and kinetics of chemical vapor deposition of pyrocarbon - II - Pyrocarbon deposition from ethylene, acetylene and 1,3-butadiene in the low temperature regime[J].Carbon: An International Journal Sponsored by the American Carbon Society,1998(3):177-199. |
| [5] | Becker A.;Huttinger KJ. .Chemistry and kinetics of chemical vapor deposition of pyrocarbon - III - Pyrocarbon deposition from propylene and benzene in the low temperature regime[J].Carbon: An International Journal Sponsored by the American Carbon Society,1998(3):201-211. |
| [6] | Becker A.;Huttinger KJ. .Chemistry and kinetics of chemical vapor deposition of pyrocarbon - IV - Pyrocarbon deposition from methane in the low temperature regime[J].Carbon: An International Journal Sponsored by the American Carbon Society,1998(3):213-224. |
| [7] | Bru¨ggert M;Hu Z;Hüttinger K J .Chemistry and kinetics of chemical vapor deposition of PyC-VI.Influence of temperature using methane as a carbon source[J].Carbon,1999,37:2021-2030. |
| [8] | Zijun Hu;Hüttinger K J .Chemistry and kinetics of chemical vapor deposition of PyC VIII:carbon deposition from methane at low pressures[J].Carbon,2001,39:433-441. |
| [9] | Benzinger W.;Huttinger K.J. .Chemistry and kinetics of chemical vapor infiltration of pyrocarbon-IV. Investigation of methane/hydrogen mixtures[J].Carbon: An International Journal Sponsored by the American Carbon Society,1999(6):931-940. |
| [10] | Sundaram K M;Froment G F .Kinetics of coke deposition in the thermal cracking of propane[J].Chemical Engineering Science,1979,34:635-644. |
| [11] | Trimm C J;Turner D L .Pyrolysis of propane emdash 2.Effect of hydrogen supplied[J].Journal of Chemical Technology and Biotechnology,1981,31:285-289. |
| [12] | Lieberman M L;Noles G T .Effect of flow rate on gas composition during the isothermal pyrolysis of methane[J].Carbon,1974,12:689-693. |
| [13] | Legrand J C;Ben-Alm R .Thermal decomposition of acetylene:formation of gaseous products and carbon black[J].Journal of Chemical Physics,1976,73:555-559. |
| [14] | Mochida I;Aoyagi Y;Yatsunami S et al.Thermal coupling of methane in novel production methods for ethylene[J].Anal Journal of Application Pyrolysis,1991,21(1/2):95-102. |
| [15] | Glasier Greg F. .Formation of pyrolytic carbon during the pyrolysis of ethane at high conversions[J].Carbon: An International Journal Sponsored by the American Carbon Society,2001(1):15-23. |
| [16] | Hoffman W P;Vastola F J;Walker P L .Pyrolysis of propylene over carbon active sites-I:Kinetics[J].Carbon,1985,23:151-161. |
| [17] | Lucas P;Marchand A .Pyrolytic carbon deposition from methane:An analytical approach to the chemical process[J].Carbon,1990,28:207-219. |
| [18] | Benzinger W.;Huttinger KJ.;Becker A. .CHEMISTRY AND KINETICS OF CHEMICAL VAPOUR DEPOSITION OF PYROCARBON .1. FUNDAMENTALS OF KINETICS AND CHEMICAL REACTION ENGINEERING[J].Carbon: An International Journal Sponsored by the American Carbon Society,1996(8):957-966. |
| [19] | Chen C J;Back M H .The simultaneous measurement of the rate of formation of carbon and of hydrocarbon products in the pyrolysis of methane[J].Carbon,1979,17:175-180. |
| [20] | Trimm D L;Turner C J .Pyrolysis of propane em dash I.Production of gases,liquids and carbon[J].Journal of Chemical Technology and Biotechnology,1981,31(04):195-204. |
| [21] | Lucas P;Marchand A .Pyrolytic carbon deposition from methane:An analytical approach to the chemical process[J].Carbon,1990,28:207-219. |
| [22] | Koyo Norinaga;Olaf Deutschmann;Klaus J. Huttinger .Analysis of gas phase compounds in chemical vapor deposition of carbon from light hydrocarbons[J].Carbon: An International Journal Sponsored by the American Carbon Society,2006(9):1790-1800. |
| [23] | Feron O;Langlais F;Naslain R .Analysis of the gas phase by in situ FTIR spectrometry and mass spectrometry during the CVD of PyC from propane[J].Chemical Vapor Deposition,1999,5(01):37-47. |
| [24] | Stein S E;Fahr A .High-Temperature Stabilities of Hydrocarbons[J].Journal of Physical Chemistry,1985,89:3714-3725. |
| [25] | Goeres A;Keller R;Sedlmayr E et al.Circumstellar carbon condensation:1 low P,T stabilities of polyaromatic hydrocarbons Polycyclic Aromat[J].Polycyclic Aromatic Compounds,1996,8:129-165. |
| [26] | Benzinger W.;Huttinger K.J. .Chemistry and kinetics of chemical vapor infiltration of pyrocarbon-VI. Mechanical and structural properties of infiltrated carbon fiber felt[J].Carbon: An International Journal Sponsored by the American Carbon Society,1999(8):1311-1322. |
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